Transportation Engineering Commons^™

Optimization Of Mix Proportion For New Jersey Precast Concrete Safety Barriers And Performance Tests Under Integral Concrete Vibrating, Chen Lin, Li Beian, Li Yuanrui, Zhao Zixiang

Journal of China & Foreign Highway

New Jersey safety barriers are the most commonly used form of guardrails in highway median separators due to their excellent safety protection.In response to the cost reduction and quality improvement，efficient and rapid preparation process，and quality issues of New Jersey precast concrete safety barriers，this article adopted the automation production process of New Jersey precast safety barriers，optimized concrete mix proportion for precast safety barriers，and studied their performance.The experimental results show that in the designed C 30 concrete，the compressive strength of the concrete mixed with 15% fly ash reaches 39.2 MPa，and th e slump reaches 185 mm.The concrete performance meets the requirements of …

Curing Law And Road Performance Of Polyurethane Mixture, Sun Shengkai, Zheng Mao, Tang Xiong, Liu Li, Zhong Shengran, Si Te

Journal of China & Foreign Highway

Polyurethane mixture is composed of polyurethane binder，rubber particles，and stones.Compared with ordinary asphalt mixture，it has the characteristics of a higher content of rubber particles and large void ratios.This article first tested the viscosity-time curve and viscosity-temperature curve of one-component polyurethane and determined the compaction temperature of the polyurethane mixture.Based on the rutting test，three-point bending test，water immersion Marshall test，freeze-thaw splitting test，and pendulum friction test，the road performance of the polyurethane mixture under different replacement amounts of rubber particles was tested.The research results show that the mixing temperature of PU- 1 polyurethane mixture can be basically controlled between 73 ℃ and 81 ℃，and it …

Elimination Method Of Temperature Lag Effect In Deformation Monitoring Data Of Cable‑Stayed Bridge Structures, Liu Hongshuang, Zhai Wenqiang, Zeng Guoliang

Journal of China & Foreign Highway

There is a temperature lag effect in the deformation monitoring data of the bridge structure.Eliminating the temperature lag effect is of great significance in the health monitoring of the bridge structure.Based on the linear correlation between the deformation of the bridge structure and the temperature，this paper applied the goodness of fit test and proposed a time-domain translation elimination method.On this basis，by taking the long-term synchronous monitoring of the tower inclination，beam end displacement，main girder deflection，and temperature data of a cable-stayed bridge as an example，this method was used to eliminate the temperature lag effect in the deformation monitoring data and compared with …

Dynamic Response Analysis Of Bridge Under Combined Action Of Random Traffic Flow And Wind Based On Simpack Platform, Xiong Tao, Han Yan, Ma Xingchuan, Li Qianming, Yan Naijie, Zhang Fei, Hu Peng

Journal of China & Foreign Highway

To deal with the time-consuming problem of calculating the dynamic responses of the bridge under the combined action of random traffic flow and wind，a steel box continuous girder bridge was taken as the engineering background，and the finite element model of the bridge and the vehicle model were established in the commercial software Ansys and SIMPACK，respectively.Then，the dynamic responses of the bridge subjected to the single vehicle load，wind loads，and multiple vehicle loads were calculated to verify the superposability of the dynamic responses of the bridge.On this basis，the Monte Carlo method was used to generate the random traffic flow samples.By using the verified …

Sensitivity Analysis Of Parameters Of Cable‑Stayed Bridges With Full Floating Spatial Frame, Liu Anqing, Yan Tengfei, Zheng Pengju, Gu Yanlin, Li Jie, Wang Qiang

Journal of China & Foreign Highway

In order to clarify the influence of design parameters on the mechanical behavior of a cable-stayed bridge of a floating system，a finite element model of the bridge was established by using the finite element analysis software MIDAS/Civil based on a single-tower double-cable plane steel-concrete composite beam cable-stayed bridge with full floating spatial frame.The sensitivity of parameters such as temperature effect，secondary dead load，and support system in the completed bridge state was analyzed and compared with the semi-floating system of the bridge.The results show that temperature and secondary dead load have a significant impact on the deflection and stress of the main …

Experimental Study On Shear Behavior Between Nrc‑Uhpc Interface, Chen Zhenkan, Li Junsheng, Shi Quan, Fang Haozhen, Mo Fan, Jiang Haibo

Journal of China & Foreign Highway

In order to investigate the effect of the screw diameter of planted bars and ultra-high performance concrete （UHPC） pouring method on the shear behavior of normal reinforced concrete （NRC） and UHPC， two groups of six push-out specimens were designed for shear behavior tests.The results show that after the failure of the concrete bonding force in the NRC-UHPC interface，the screw can maintain shear behavior so that the failure process of the specimen after the load reaches the peak shows ductile characteristics.For specimens with screw diameters of 12 mm and 16 mm，greater screw diameter indicates higher shear capacity of the specimens and …

Design And Construction Process Of Cross‑Beam Supports For Main Tower Of Changtai Changjiang River Bridge, Zeng Jian, Hu Pei, Wang Chao

Journal of China & Foreign Highway

The construction of the lower cross-beam structure of the main tower of Changtai Changjiang River Bridge has the characteristics of high construction height，large amount of concrete earth volume，and difficult control of down-warping deformation.In order to implement the pouring of the lower cross-beam of the main tower，floor-type steel pipe supports were set at the lower cross-beam，which were used to support the lower cross-beam formwork and bear the load during the concrete pouring.Through the finite element software analysis and calculation，it was found that the asymmetric deformation of the main structure of the lower cross-beam could be effectively controlled，and the overall force of …

Segment Connection Mod E For Stiffening Girder Hoisting Construction Of Long‑Span Steel Truss Girder Suspension Bridge, Shao Guangmiao, Pan Q Uan, Yan Donghuang, Xu Hongsheng

Journal of China & Foreign Highway

In the process of stiffening girder construct ion of a long-span steel truss girder suspension bridge，different connection modes of stiffening girder segments will directly affect the internal force，alignment，and bridge state of the structure during construction.By taking the construction of the stiffening girder of a bridge as the research background，the finite element model of the whole process of the bridge was established.The advantages and disadvantages of the segmented hinge method and the segmented rigid connection method were compared，and the two-two segmented rigid connection scheme was proposed.On this basis，according to the changing law of steel truss section alignment and lower chord opening …

Research On T‑Beam System With Diaphragm Based On Intelligent Construction, Liu Lang, Tao Qiyu, Xu Qigang

Journal of China & Foreign Highway

The traditional precast T-beam faces issues such as excessive diaphragms，difficult formwork installation and removal，and low levels of intelligence in intelligent bridge construction.To address these issues，this paper focused on the optimization of the number of diaphragms and the application of prefabricated diaphragms.By analyzing different diaphragm configuration schemes and comparing the contributions of prefabricated diaphragms and precast diaphragms to the lateral stiffness of the bridge，this paper deeply explored the impact of diaphragms on bridge performance.The research results indicate that the T-beam system with fewer diaphragms is feasible in intelligent construction，but the system without diaphragms places higher demands on the performance of bridge …

Determination Of Manufacturing Parameters Of Large Section Of Continuous Steel Box Beam With Variable Section In Shenzhen‑Zhongshan Passage, Dong Chuangwen, Chen Long, Li Chuanxi

Journal of China & Foreign Highway

Accurate calculation of manufacturing parameters is the key to the efficient，high-precision，and rapid installation of large sections of continuous steel box beam bridges.Taking the steel box beam with the variable section in Shenzhen-Zhongshan Passage as the background，this paper first established a finite element model of the beam element in the whole construction process to obtain the pre-camper.Secondly，the average neutral axis position was calculated based on the height of the neutral axis of each beam section.Then，according to the deformation characteristic that the beam length remained unchanged at the mean neutral axis，the pre-camber was superimposed at the mean neutral axis to get the …

Key Technology For Construction Of New Single‑Wall Steel Suspended Box Cofferdam With High Pile Tied Beams In Deep Water, Yang Jinlong, Zhao Lin, Jiang Qunlong

Journal of China & Foreign Highway

In order to ensure the safe，efficient，and economical completion of the construction of the high pile tied beam of Muping Xiangjiang River Bridge in deep water，a new type of single-wall steel suspended box cofferdam was designed to act as the water retaining and enclosure structure during high pile tied beam construction according to the characteristics of deep water level and shallow stratum cover layer at the high pile tied beam location.Through the innovative design of steel casing on the bottom of the steel suspended box cofferdam，the design height of the wall panel and the amount of steel input were reduced.On the …

3d Reconstruction Method Of Tunnel Surrounding Rock Fracture Based On Vtk, Liu Houxiang, Su Heng

Journal of China & Foreign Highway

Fracture parameters are important reference factors for surrounding rock stability analysis.To realize the visualization analysis of surrounding rock fractures，this paper proposed a three-dimensional （3D） reconstruction method of surrounding rock fractures based on the visualization toolkit （VTK）.Firstly，the collected tunnel surrounding rock images were preprocessed by OpenCV for image grayscale and noise reduction.Secondly，the Otsu method and the open operation in morphology were used to segment the image，and the complete surrounding rock fracture map was obtained.Then，the median method was used to replace the linear interpolation method with the traditional Marching Cubes algorithm in VTK to calculate the equivalent point，and the improved Marching Cubes …

Surface Grouting Reinforcement Technology For Shallowly Buried Tunnel In Coastal Zone, Xiang Ze, Deng Shiping, Sheng Zhang, Zhou Ye, Wang Wei, Pei Yabing

Journal of China & Foreign Highway

The Ⅵ level surrounding rock section of a project water intake tunnel is located in the coastal zone，with thick overlying sand layers，broken surrounding rock，and other characteristics.To address these issues，laboratory tests were conducted to explore the effect of water glass volume dosing on the final setting time and strength of cement-sodium silicate （CS） liquid slurry，and field tests were carried out for a comprehensive analysis of grouting methods.The constraint-dispersion mode was finally determined to divide the grouting area into several small grouting units.Advance plastic pipe grouting reinforcement was performed according to the grouting sequence of the outermost circle hole interval first，followed by …

Key Technology For Incremental Launching Construction Of Double Guide Beam Of Steel Box Girder, Sun Xiaoqiang, Yue Xinxing

Journal of China & Foreign Highway

By taking the incremental launching construction of the steel box girder at the 6th hole of the approach bridge of Baoji Taigu Bridge as the engineering background，the original plan adopted single-guide beam multi-point walking incremental launching technology for assembly and incremental launching on the prestressed reinforced concrete beam of the adjacent hole.Since the middle span of the concrete beam cannot withstand the concentrated force at the incremental launching points，the multi-guide beam multi-point walking incremental launching technology was finally used to arrange the incremental launching points at the transverse diaphragm plate of the end of the concrete beam.By increasing the incremental …

Influence Factors Of Carbonization Of Tunnel Segment Structure And Life Prediction Analysis, Li Dongbiao, Miao Miao, Shen Caihua, Chen Wei

Journal of China & Foreign Highway

There are many factors that affect the carbonization life of concrete segments in underwater tunnels，and the prediction methods are not uniform.In this paper，combined with actual engineering，the influencing factors and laws of carbonization of concrete segments in underwater tunnels were analyzed，and three methods for predicting the life of concrete segments were established with the crack limit as the control target.The prediction results of the three methods were compared.The results show that the influence of the temperature and CO2 concentration in the tunnel predicted by the three methods on the life of the tunnel lining structure is basically consistent with the existing …

Emergency Vehicle Dispatching Model Considering Demand Urgency And Delivery Fairness, Long Kejun, Liu Jia, Gao Zhibo, Chen Suqian, Zhang Zhonggen

Journal of China & Foreign Highway

In emergency vehicle dispatching after unexpected events，it is crucial to prioritize critical nodes with high demand urgency while minimizing excessive delivery delays at other nodes to prevent secondary impacts.On this basis，this study developed an emergency vehicle dispatching model that considered demand urgency and delivery delay fairness.Firstly，the entropy weight-TOPSIS method was used to calculate the demand urgency for each node，and a delivery delay balance index was introduced to minimize disparities in delivery delays between nodes.Secondly，a multi-objective optimization model was established with total delivery time，overall cost，and delivery delay balance as objectives，while considering constraints such as inventory levels at distribution centers and route …

Research And Practice On Demolition Of Lane Separator In Same Direction Along Zhengzhou‒Luoyang Section Of Lianyungang‒Khorgos Expressway, Zhang Nan, Ji Xiang, Ma Gang

Journal of China & Foreign Highway

In order to solve the problem arising after the demolition and closure of the lane separator in the same direction along the expressway，this paper systematically introduced the reconstruction method of the lane separator in the same direction by studying the overhaul project along Zhengzhou-Luoyang section of Lianyungang‒Khorgos Expressway.The paper explored the main diseases and potential safety hazards existing in the lane separator in the same direction by checking the compliance of specifications，analyzing the traffic operation status，exploring the characteristics of traffic accidents，and investigating the traffic safety facilities.On this basis，it demonstrated the feasibility of demolishing the lane separator in the same direction.According …

Linkage Control Method For Expressway Toll Stations And Plane Intersections, Lei Qing, Wang Zhaoyong, Wu Yurong, Jiang Weiwei, Luo Zhongbin

Journal of China & Foreign Highway

In order to solve the problem of vehicle queuing overflow caused by the mismatch between the expressway toll stations and the capacity of plane intersections，the formula for calculating the maximum queue length was given by analyzing the traffic operation characteristics between toll stations and plane intersections and considering vehicles ’ lane-changing behavior.Due to the strong coupling of the traffic operation between toll stations and plane intersections caused by a short distance between them，a unified linkage control optimization model was established.The research shows that if the queue length in the connecting direction of the plane intersections exceeds the allowable maximum queue …

Working Properties Of Steel Tube Batter Piles With Concrete Infill Based On Abaqus, Yang Meiliang, Li Liemin, Sun Kunjiang, Han Rui, Zhong Yang

Journal of China & Foreign Highway

In order to explore the respons e characteristics of steel tube batter piles with concrete infill under vertical load，the steel tube batter pile with concrete infill used in Saribas Bridge in Malaysia was taken as the research object.Based on the numerical simulation method，the frictional resistance of the inner and outer walls of the steel tube，the frictional resistance around the pile at the section，and the bending moment bearing ratio between the steel tube and the concrete core of this type of batter pile under vertical load were studied.The results show that the passive-side frictional resistance of the 0–15 m pile section …

Sustainable And User-Driven Scope Development Framework For Engineering Design Services Of Transportation Infrastructure Projects, Ahmad Zaki Ghafari

All Dissertations

Rapid economic growth has led to a significant increase in transportation demands, exerting unprecedented pressure on infrastructure systems in the United States. State transportation agencies play a vital role in maintaining and developing transportation infrastructure networks within their regions. State transportation agencies face immense pressure from federal and state governments, elected officials, and the public to deliver projects efficiently and within budget. State transportation agencies rely on professional consultants for engineering design services. Engineering design services for transportation infrastructure projects are delayed due to incomplete inaccurate scope. For state Department of Transportation (DOTs), a streamlined scope development process is essential …

Next Generation Permeable Pavement For Enhanced Durability And Functionality, S M Tanvir

LSU Master's Theses

Porous Asphalt Concrete (PAC), also known as Open-Graded Friction Course (OGFC), is known for its high permeability, which provides benefits such as enhanced rainwater drainage, improved skid resistance, and reduced hydroplaning risks. These characteristics are due to its high air void content, allowing water to flow through the pavement and reducing splash, spray, and noise compared to conventional asphalt mixes. However, this high air void content also contributes to durability concerns, such as raveling, stripping, and clogging, which can reduce service life and increase costs, making OGFC more expensive than conventional asphalt mixtures.

This research focuses on identifying the failure …

Progress And Prospects Of Road Engineering Disease Treatment Technology In Permafrost Regions, Gao Feng, Zeng Xianzhang, Zhong Wenhua, Huang Shengyong, Zhang Junhui

Journal of China & Foreign Highway

Freeze-thaw disasters are key issues affecting the service performance and operational safety of road projects in permafrost regions.Under the combined influence of warming and humidification of the permafrost environment and engineering thermal effects，the degradation of permafrost is accelerating，exacerbating the risk of road freeze-thaw diseases.Roads in these regions are more frequently maintained and repaired to ensure service performance，with a service life lower than designed.Therefore，deepening the understanding of the disaster mechanism of road geotechnical structures and strengthening the study on engineering disease treatment technology are of great significance in promoting the construction and maintenance of high-quality and high-grade highways in frozen regions.This …

Treatment Methods Of Unstable Expansive Soil Slope Excavation In Overlying Rock Layer In Alpine Region, Shi Xiaobo, Cui Guangyan, Mou Chao, Wen Ye, Xie Feng, Fu Xiaoyang

Journal of China & Foreign Highway

To deeply study the treatment method for instability of highway cutting slope under the condition of expansive soil overlying rock layer in an alpine region，the comprehensive treatment method of unstable slope under this bad geology was put forward based on the unstable slope project of Zhangbei‒Shangyi Expressway.The governance protection structure consisted of a rigid protection system，drainage system，thermal insulation system，flexible protection system，and waterproof system.The rigid protection system was an anti-slide pile setting at the height of 1/3 of the first grade slope，of which parameters were calculated by cutting the slope of the rock layer in the unstable area to reduce the …

Review Of Snow And Ice Melting Techniques For Road And Bridge In Cold Regions, Tang Liyun, Shao Haitao, Tang Huaming, Qiu Peiyong, Du Xiaoqi, Zhang Lei, Peng Hui

Journal of China & Foreign Highway

Snow and ice melting of road and bridge surfaces is crucial for traffic safety，but current research on snow and ice melting techniques mainly focuses on engineering effects and technical evaluation，without the analysis and elaboration from the perspective of their mechanisms.To this end，based on the different mechanisms，this study divided snow and ice melting techniques into three types and summarized them：passive deicing，active deicing，and energy utilization deicing.This study systematically evaluated the advantages and disadvantages of traditional deicing methods such as deicing agents and mechanical deicing，analyzed two active deicing techniques，namely inhibitive freezing pavement and phase change material pavement，discussed the environmental-friendly method for road deicing …

Properties And Application Of Cement Improved Loess Under Low Temperature Environment In Cold Region, Li Xiangyang

Journal of China & Foreign Highway

According to the cold climate and low annual average temperature in cold regions of China，the field curing conditions of cement improvement of collapsibility loess under low temperature，room temperature，and medium temperature were simulated at 5 ℃，10 ℃，20 ℃，and 30 ℃，respectively.Based on laboratory experiments，this study analyzed the effects of curing temperature，cement content，and curing age on RCBR，unconfined compressive strength，and dynamic resilience modulus of cement improved loess.The effects of cement content and curing temperature on freeze-thaw durability and erosion resistance of cement improved loess were studied by the freeze-thaw cycle test and dynamic water erosion test.Combined with the laboratory results，the 4% and 5% cement …

Effect Of Chloride Ions On Salt Expansion Of Salinized Subgrade Fill Soil In Cold Regions, Hu Wenzhu, Wang Zhaowei, Cao Yong, Zhang Jing, Bai Ruiqiang

Journal of China & Foreign Highway

Salinized subgrade fill soil in cold regions typically comprises composite saline soil rich in sodium chloride and sodium sulfate.This study aimed to explore the mechanism of the effect of chloride ion content on salt expansion of the salinized subgrade in cold regions.Based on the calculation theory of the sodium chloride-sodium sulfate-water ternary system solution in the Pitzer ion model and combined with the FREZCHEM model，the study quantitatively analyzed the intrinsic connection between water activity，freezing factor，and supersaturation ratio with temperature and concentration ratio （η=mCl-/mSO2-4）.It investigated the variation patterns of the freezing temperature and crystallization supersaturation ratio of composite saline soil with …

Model Test On Soil Deformation Mechanism And Damage Mode Caused By Mud Leakage From Drilled Piles In Karst Area, Jiang Mingying, Chen E ’Mei, Liu Yongcheng, Zhu Yadong, Jiang Wenkui, Xie Ruiting

Journal of China & Foreign Highway

Pile holes are often drilled through cavities in karst areas，which induces mud leakage and causes hole wall instability，ground collapse，or equipment trapping and hinders smooth construction.It is important to know the collapse mechanism of boreholes due to mud leakage，so as to optimize and determine the construction process of pile holes.In this paper，indoor model tests were used to study the deformation mechanism and damage mode of soil caused by drilling through cavities and mud leakage in pile holes under the conditions of upper clay and lower sandy soil in the karst area，so as to provide an experimental basis for the decision of …

Back‑Calculation Of Subgrade Modulus Based On Genetic Algorithm And Viscoelasticity Theory, Dai Fugui, Wang Xihui, Wu Yaguang, Li Hai

Journal of China & Foreign Highway

To improve the applicability of the PFWD detection method for the back-calculation of subgrade modulus，taking the subgrade splicing project of the west loop line in Nairobi as an example，this paper adopted 3D Kelvin viscoelasticity model and quasi-static response analysis to deduce the displacement function of viscoelastic subgrade under long-term fixed loads，and combined the principle of liner superposition of viscoelasticity with genetic algorithm to propose a new method based on multi-population genetic algorithm for the modulus back-calculation of viscoelastic subgrade.Among them，the corresponding program for back-calculation was written by Matlab.The comparison between theoretical derivation and field tests shows that the peak value …

Correlation Between Pavement Distress And Structural Hidden Distress, Liu Xianming, Xia Han, Hu Dongping, Yan Chen, Yang Rui, Zhong Xinran

Journal of China & Foreign Highway

The hidden distress in the pavement structure does great harm to the performance and service life of the road.In this work，based on the statistical idea of pavement distress rate in the Highway Performance Assessment Standards （JTG 5210—2018），an index of characterizing hidden distress in the pavement structure，namely pavement structure distress rate，was proposed.Based on the actual highway inspection project，the pavement distress and the hidden distress in the depth of 1 m below the pavement of a two-way four-lane highway with a length of 38 km were studied.The overall situation of pavement distress and hidden distress and their spatial distribution were analyzed statistically …

Review Of Evaluation Methods For Mixing Workability Of Asphalt Mixture, Dong Fuqiang, Zu Yuanzhe, Yu Xin, Chen Bei, Liu Lin

Journal of China & Foreign Highway

To clarify the evaluation methods an d research status of mixing workability of asphalt mixture， by consulting relevant research literature in China and abroad and analyzing different evaluation methods，indexes，and research findings of the workability of asphalt mixture，the applicability and evaluation effects of different workability evaluation methods were systematically summarized，and the comparative analysis and comprehensive review were made on the main influencing factors of the mixing workability.The results show that in most evaluation methods for the mixing workability of asphalt mixture，corresponding indexes are constructed to quantitatively evaluate the workability by quantifying the resistance or energy consumption in the mixing process.Besides，in some …